Low
S.30 on Glow-worm Energy7 Combi

Your boiler is perfectly safe, but it is currently being prevented from turning on the heating because your room thermostat or smart controller is telling it to stay off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Room thermostat is blocking heating mode.

From this model's manual
Verified against the Glow Worm Energy7 Combi installation & service manual, page 51.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate your room thermostat or smart home app.Increase the target temperature to several degrees above the current room temperature.Check if the thermostat batteries need replacing or if the wireless connection has dropped.

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